Revert "Add timestamp in scan results"

Temporarily reverting this until all devices switch to using wpa_supplicant_8.

This reverts commit b31f78f93768fef269617ec788a5c6655a375f80.

Change-Id: I33fcb8415288d95289dcd46fa71e950e0f2b87ec
Signed-off-by: Iliyan Malchev <malchev@google.com>

3 files changed, 115 insertions, 129 deletions

diff --git a/wifi/java/android/net/wifi/ScanResult.java b/wifi/java/android/net/wifi/ScanResult.java
index 3e20756..32261de 100644
--- a/wifi/java/android/net/wifi/ScanResult.java
+++ b/wifi/java/android/net/wifi/ScanResult.java
@@ -47,37 +47,19 @@ public class ScanResult implements Parcelable {
     public int frequency;
 
     /**
-     * Time Synchronization Function (tsf) timestamp in microseconds when
-     * this result was last seen.
-     */
-     public long timestamp;
-
-    /**
      * We'd like to obtain the following attributes,
      * but they are not reported via the socket
      * interface, even though they are known
      * internally by wpa_supplicant.
      * {@hide}
      */
-    public ScanResult(String SSID, String BSSID, String caps, int level, int frequency, long tsf) {
+    public ScanResult(String SSID, String BSSID, String caps, int level, int frequency) {
         this.SSID = SSID;
         this.BSSID = BSSID;
         this.capabilities = caps;
         this.level = level;
         this.frequency = frequency;
-        this.timestamp = tsf;
-    }
-
-    /** copy constructor {@hide} */
-    public ScanResult(ScanResult source) {
-        if (source != null) {
-            SSID = source.SSID;
-            BSSID = source.BSSID;
-            capabilities = source.capabilities;
-            level = source.level;
-            frequency = source.frequency;
-            timestamp = source.timestamp;
-        }
+        //networkConfig = null;
     }
 
     @Override
@@ -94,9 +76,7 @@ public class ScanResult implements Parcelable {
             append(", level: ").
             append(level).
             append(", frequency: ").
-            append(frequency).
-            append(", timestamp: ").
-            append(timestamp);
+            append(frequency);
 
         return sb.toString();
     }
@@ -113,7 +93,6 @@ public class ScanResult implements Parcelable {
         dest.writeString(capabilities);
         dest.writeInt(level);
         dest.writeInt(frequency);
-        dest.writeLong(timestamp);
     }
 
     /** Implement the Parcelable interface {@hide} */
@@ -125,8 +104,7 @@ public class ScanResult implements Parcelable {
                     in.readString(),
                     in.readString(),
                     in.readInt(),
-                    in.readInt(),
-                    in.readLong()
+                    in.readInt()
                 );
             }
 
diff --git a/wifi/java/android/net/wifi/WifiNative.java b/wifi/java/android/net/wifi/WifiNative.java
index 1b7e378..84c565b 100644
--- a/wifi/java/android/net/wifi/WifiNative.java
+++ b/wifi/java/android/net/wifi/WifiNative.java
@@ -197,22 +197,8 @@ public class WifiNative {
         return null;
     }
 
-    /**
-     * Format of results:
-     * =================
-     * bssid=68:7f:74:d7:1b:6e
-     * freq=2412
-     * level=-43
-     * tsf=1344621975160944
-     * age=2623
-     * flags=[WPA2-PSK-CCMP][WPS][ESS]
-     * ssid=zubyb
-     *
-     * RANGE=ALL gets all scan results
-     * MASK=<N> see wpa_supplicant/src/common/wpa_ctrl.h for details
-     */
     public String scanResults() {
-        return doStringCommand("BSS RANGE=ALL MASK=0x1986");
+        return doStringCommand("SCAN_RESULTS");
     }
 
     public boolean startDriver() {
diff --git a/wifi/java/android/net/wifi/WifiStateMachine.java b/wifi/java/android/net/wifi/WifiStateMachine.java
index bdb02c5..28c1c5c 100644
--- a/wifi/java/android/net/wifi/WifiStateMachine.java
+++ b/wifi/java/android/net/wifi/WifiStateMachine.java
@@ -891,13 +891,7 @@ public class WifiStateMachine extends StateMachine {
      * TODO: doc
      */
     public List<ScanResult> syncGetScanResultsList() {
-        synchronized (mScanResultCache) {
-            List<ScanResult> scanList = new ArrayList<ScanResult>();
-            for(ScanResult result: mScanResults) {
-                scanList.add(new ScanResult(result));
-            }
-            return scanList;
-        }
+        return mScanResults;
     }
 
     /**
@@ -1363,103 +1357,131 @@ public class WifiStateMachine extends StateMachine {
         mContext.sendStickyBroadcast(intent);
     }
 
-    private static final String BSSID_STR = "bssid=";
-    private static final String FREQ_STR = "freq=";
-    private static final String LEVEL_STR = "level=";
-    private static final String TSF_STR = "tsf=";
-    private static final String FLAGS_STR = "flags=";
-    private static final String SSID_STR = "ssid=";
-    private static final String DELIMITER_STR = "====";
     /**
-     * Format:
-     * bssid=68:7f:76:d7:1a:6e
-     * freq=2412
-     * level=-44
-     * tsf=1344626243700342
-     * flags=[WPA2-PSK-CCMP][WPS][ESS]
-     * ssid=zfdy
-     * ====
-     * bssid=68:5f:74:d7:1a:6f
-     * freq=5180
-     * level=-73
-     * tsf=1344626243700373
-     * flags=[WPA2-PSK-CCMP][WPS][ESS]
-     * ssid=zuby
-     * ====
+     * Parse the scan result line passed to us by wpa_supplicant (helper).
+     * @param line the line to parse
+     * @return the {@link ScanResult} object
      */
-    private void setScanResults(String scanResults) {
-        String bssid = "";
-        int level = 0;
-        int freq = 0;
-        long tsf = 0;
-        String flags = "";
-        String ssid = "";
-
-        if (scanResults == null) {
-            return;
-        }
-
-        synchronized(mScanResultCache) {
-            mScanResults = new ArrayList<ScanResult>();
-            String[] lines = scanResults.split("\n");
-
-            for (String line : lines) {
-                if (line.startsWith(BSSID_STR)) {
-                    bssid = line.substring(BSSID_STR.length());
-                } else if (line.startsWith(FREQ_STR)) {
-                    try {
-                        freq = Integer.parseInt(line.substring(FREQ_STR.length()));
-                    } catch (NumberFormatException e) {
-                        freq = 0;
-                    }
-                } else if (line.startsWith(LEVEL_STR)) {
+    private ScanResult parseScanResult(String line) {
+        ScanResult scanResult = null;
+        if (line != null) {
+            /*
+             * Cache implementation (LinkedHashMap) is not synchronized, thus,
+             * must synchronized here!
+             */
+            synchronized (mScanResultCache) {
+                String[] result = scanResultPattern.split(line);
+                if (3 <= result.length && result.length <= 5) {
+                    String bssid = result[0];
+                    // bssid | frequency | level | flags | ssid
+                    int frequency;
+                    int level;
                     try {
-                        level = Integer.parseInt(line.substring(LEVEL_STR.length()));
+                        frequency = Integer.parseInt(result[1]);
+                        level = Integer.parseInt(result[2]);
                         /* some implementations avoid negative values by adding 256
                          * so we need to adjust for that here.
                          */
                         if (level > 0) level -= 256;
-                    } catch(NumberFormatException e) {
+                    } catch (NumberFormatException e) {
+                        frequency = 0;
                         level = 0;
                     }
-                } else if (line.startsWith(TSF_STR)) {
-                    try {
-                        tsf = Long.parseLong(line.substring(TSF_STR.length()));
-                    } catch (NumberFormatException e) {
-                        tsf = 0;
-                    }
-                } else if (line.startsWith(FLAGS_STR)) {
-                    flags = line.substring(FLAGS_STR.length());
-                } else if (line.startsWith(SSID_STR)) {
-                    ssid = line.substring(SSID_STR.length());
-                    if (ssid == null) ssid = "";
-                } else if (line.startsWith(DELIMITER_STR)) {
-                    if (bssid != null) {
-                        String key = bssid + ssid;
-                        ScanResult scanResult = mScanResultCache.get(key);
-                        if (scanResult != null) {
-                            scanResult.level = level;
-                            scanResult.SSID = ssid;
-                            scanResult.capabilities = flags;
-                            scanResult.frequency = freq;
-                            scanResult.timestamp = tsf;
+
+                    /*
+                     * The formatting of the results returned by
+                     * wpa_supplicant is intended to make the fields
+                     * line up nicely when printed,
+                     * not to make them easy to parse. So we have to
+                     * apply some heuristics to figure out which field
+                     * is the SSID and which field is the flags.
+                     */
+                    String ssid;
+                    String flags;
+                    if (result.length == 4) {
+                        if (result[3].charAt(0) == '[') {
+                            flags = result[3];
+                            ssid = "";
                         } else {
+                            flags = "";
+                            ssid = result[3];
+                        }
+                    } else if (result.length == 5) {
+                        flags = result[3];
+                        ssid = result[4];
+                    } else {
+                        // Here, we must have 3 fields: no flags and ssid
+                        // set
+                        flags = "";
+                        ssid = "";
+                    }
+
+                    // bssid + ssid is the hash key
+                    String key = bssid + ssid;
+                    scanResult = mScanResultCache.get(key);
+                    if (scanResult != null) {
+                        scanResult.level = level;
+                        scanResult.SSID = ssid;
+                        scanResult.capabilities = flags;
+                        scanResult.frequency = frequency;
+                    } else {
+                        // Do not add scan results that have no SSID set
+                        if (0 < ssid.trim().length()) {
                             scanResult =
                                 new ScanResult(
-                                        ssid, bssid, flags, level, freq, tsf);
+                                    ssid, bssid, flags, level, frequency);
                             mScanResultCache.put(key, scanResult);
                         }
-                        mScanResults.add(scanResult);
-                    }
-                    bssid = null;
-                    level = 0;
-                    freq = 0;
-                    tsf = 0;
-                    flags = "";
-                    ssid = "";
+                    }
+                } else {
+                    loge("Misformatted scan result text with " +
+                          result.length + " fields: " + line);
+                }
+            }
+        }
+
+        return scanResult;
+    }
+
+    /**
+     * scanResults input format
+     * 00:bb:cc:dd:cc:ee       2427    166     [WPA-EAP-TKIP][WPA2-EAP-CCMP]   Net1
+     * 00:bb:cc:dd:cc:ff       2412    165     [WPA-EAP-TKIP][WPA2-EAP-CCMP]   Net2
+     */
+    private void setScanResults(String scanResults) {
+        if (scanResults == null) {
+            return;
+        }
+
+        List<ScanResult> scanList = new ArrayList<ScanResult>();
+
+        int lineCount = 0;
+
+        int scanResultsLen = scanResults.length();
+        // Parse the result string, keeping in mind that the last line does
+        // not end with a newline.
+        for (int lineBeg = 0, lineEnd = 0; lineEnd <= scanResultsLen; ++lineEnd) {
+            if (lineEnd == scanResultsLen || scanResults.charAt(lineEnd) == '\n') {
+                ++lineCount;
+
+                if (lineCount == 1) {
+                    lineBeg = lineEnd + 1;
+                    continue;
                 }
+                if (lineEnd > lineBeg) {
+                    String line = scanResults.substring(lineBeg, lineEnd);
+                    ScanResult scanResult = parseScanResult(line);
+                    if (scanResult != null) {
+                        scanList.add(scanResult);
+                    } else {
+                        //TODO: hidden network handling
+                    }
+                }
+                lineBeg = lineEnd + 1;
             }
         }
+
+        mScanResults = scanList;
     }
 
     /*
@@ -2805,7 +2827,7 @@ public class WifiStateMachine extends StateMachine {
             if (DBG) log(getName() + "\n");
             mIsRunning = false;
             updateBatteryWorkSource(null);
-            mScanResults = new ArrayList<ScanResult>();
+            mScanResults = null;
 
             if (mP2pSupported) mWifiP2pChannel.sendMessage(WifiStateMachine.CMD_DISABLE_P2P);
             mContext.unregisterReceiver(mScreenReceiver);